I love battlefield. I was an uber good medic in BF2. Same with BF3. The question I have is can you still revive people in BF4?
Yes. They've made it better - once you press to revive, your character rubs the paddles, then zaps - a nod both to realism, and to preventing players from reviving others too quickily.
This game differs greatly with achievements and unlocks. You unlock "packs" of sorts, for classes, gadgets etc. As you progress with a certain class/weapon, packs will become available for you to 'open' and use.
Also, squad perks are now selected via 'packs' instead of single perks, and are 'earned' each round. For example, an assault squad pack (this information might not be accurate, but let's ignore that for this example) might include Sprint, Ammo, xx and xx perks. During each round, you'll see a small green bar that will slowly fill as the round progresses and your squad/team do well. Once the bar reaches each perk (situated as increments along the bar, levels 1 through 4 kind of thing), they will be come available and in use.
It's interesting...